The development and implementation of fiber optics has radically changed the world. Using fiber optics, data, voice and video information can be digitized, transmitted and received almost instantly throughout the world. With the development of fiber optics, transmission speeds are typically limited only by the speed and capacity of the sending and receiving means. At the same time, the optical fiber used in fiber optic systems is more reliable and more secure than traditional copper transmission lines. While the use of optical fiber for signal transmission has many advantages, the costs associated with the installation and maintenance of optical links can be significant, particularly when compared to copper links. This is often due to the lack of effective diagnostic tools for troubleshooting optical fiber systems.
A basic fiber optic system comprises three main components: a transmitter, a transmission medium, and a receiver. A fiber optic transmitter converts an electrical signal to a light signal, which is subsequently emitted from the transmitter. The light signal is typically within the non-visible spectrum such that there is no visible indication to anyone proximate the fiber optic system that signal is present. The transmission medium carries the light signal from the transmitter to the receiver. The receiver converts the light signal into an electrical signal. While the concept of a basic fiber optic system is easy to envision, actual installation and troubleshooting of a fiber optic system can be a complex and expensive process.
Optical fiber is generally constructed in a core and cladding configuration where two dissimilar types of glass are drawn together in a single strand. Because of the differences in the two types of glass, light entering the core of the strand will propagate along the strand by means of reflection until it reaches the far end of a strand or encounters a fault. While optical fiber, a glass strand generally 125 μm in diameter, can be a delicate structure, it tends to be robust in practical application because it is protected by a polymer buffer and up to several layers of jacketing.
The robust buffer and jacket design of commercial fiber optic cables virtually eliminates problems within the cable itself. Instead, the vast majority of problems occur in or near a patch cabinet or a splice enclosure where the cable is stripped away and handling of individual strands must occur.